Baker & Hostetler and partner John Moscow have been disqualified from defending real estate companies allegedly involved in laundering proceeds of a Russian fraud scheme after a federal judge found the firm’s defense strategy involves attacks against a former client.

Southern District Judge Thomas Griesa said Friday he did not take the decision to disqualify the firm lightly, but “there is now a very real possibility that Baker Hostetler will be in a position where it would be trying to show that its current clients … are not liable” by attacking its former client.